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Genetic Drift

updated: June 23, 2022

Definition

Genetic drift is a mechanism of evolution characterized by random fluctuations in the frequency of a particular version of a gene (allele) in a population. Though it primarily affects small, isolated populations, the effects of genetic drift can be strong, sometimes causing traits to become overwhelmingly frequent or to disappear from a population.



Narration

Genetic drift. I think the best way to look at it is to look at genetic drift as an evolutionary process. It is really the shuffling of our DNA frequency from one generation to the other. And as a result of this chance event, you know, you can emphasize it in things, you know, in the population. So it is in things. Something that may cause a particular type of gene to be more dominant or a particular type disease to disappear from a population. So again, it is a chance event, and it is an evolutionary process.